Bag for bag-in-box and bag-in-box

Abstract

The bag for bag-in-box of this invention comprises: a bag body composed of flat portions and side portions each having a folding line along which the side portion is folded inward; oblique seal portions provided at respective corner portions of the bag body, the oblique seal portion being formed by obliquely cutting-off the respective corner portions; and a triangular fin portion integrally formed with the oblique seal portion; wherein the flat portion and the side portion are composed of several sheets of synthetic resin films that are superposed to each other. The dimensions of the bag shall be set within a predetermined range so as to meet the International Standard of a pallet. The opening portion to be formed on the outer box of the bag-in-box has a size enabling to sufficiently draw out a spout and the bag body portion around the spout to form a funnel-shape. According to the present invention, there can be provided an inner bag for a bag-in-box excellent in shock resistance, content discharging property and self-supporting property at a time when the inner bag is filled with the content.

What is claimed is: 
     
       1. A bag used as an inner bag for a bag-in-box having an outer box and the inner bag accommodated within the outer box, said bag comprising: a four-side-seal type bag body composed of a pair of opposing flat portions constituting front and back side portions and two side portions connecting front and back side portions at both side ends thereof and respectively having folding lines along which the side portions are folded inward;   oblique seal portions provided at respective corner portions of the bag body; and   triangular fin portions formed at respective corner portions of the bag body;   wherein said flat portions and said side portions are composed of at least two sheets of synthetic resin films that are superposed to each other in a non-bonded state;   wherein said oblique seal portion is formed such that the two side portions are folded along the folding line, opposing inner surfaces of the bag body are bonded to each other between a first arbitrary point on top seal portion or bottom seal portion to a second arbitrary point on a side seal portion so as to obliquely connect said top seal portion or bottom seal portion and the side seal portion, the oblique seal portion being linear;   wherein said triangular fin portion being defined by the side seal portion, the oblique seal portion and one of the top seal portion and the bottom seal portion;   and wherein each of said flat portions and said side portions has a shape of a square or a rectangle, and the bag being a cube or a rectangular parallelepiped when filled.   
     
     
       2. A bag for the bag-in-box according to claim 1, wherein the first arbitrary point is located within 1 cm of the folding line when said bag is folded. 
     
     
       3. A bag for the bag-in-box according to claim 1, wherein opposing top portions of the corner portions formed at front and back sides of the bag body are bonded to each other. 
     
     
       4. A bag for the bag-in-box according to claim 1, wherein at least one band-shaped gas-filled layer extending toward vertical direction of the bag body is provided on each of a pair of flat portions and two side portions, respectively. 
     
     
       5. A bag for the bag-in-box according to claim 1, wherein a bilaterally pair of hanger portions are formed on at least one of said top and bottom sides of the bag body, said hanger portions being formed by bonding said opposing triangular fin portions of both front and back sides to each other at the top portions of the corner portions, and by further bonding said opposing triangular fin portions at another portion consisting of at least one portion on said top seal portion or said bottom seal portion. 
     
     
       6. A bag for the bag-in-box according to claim 1, wherein a punched hole is formed on at least one of the triangular fin portions. 
     
     
       7. A bag for the bag-in-box according to claim 1, wherein said synthetic resin film contains at least one metal foil layer. 
     
     
       8. A bag for the bag-in-box according to claim 1, wherein an angle lying between the top seal portion and the oblique seal portion is 45-55 degrees, and an angle lying between the bottom seal portion and the oblique seal portion is 40-50 degrees. 
     
     
       9. A bag for the bag-in-box according to claim 1, wherein horizontal dimension of the flat portion is 260-340 mm, horizontal dimension of the side portion is 180-260 mm, vertical dimension of each of the flat and side portions is 490-660 mm, each of said dimensions being expressed as a substantial dimension which is defined by subtracting width of the seal portion from actual dimension of each portion, and a shape of the bag after filling up content therein is a rectangular parallelepiped. 
     
     
       10. A bag for bag-in-box according to claim 1, wherein horizontal dimension of the flat portion is 190-270 mm, horizontal dimension of the side portion is 140-220 mm, vertical dimension of each of the flat and side portions is 330-600 mm, each of said dimensions being expressed as a substantial dimension which is defined by subtracting width of the seal portion from actual dimension of each portion, and a shape of the bag after filling up content therein is a rectangular parallelepiped.